KR20040101459A - Fuel cell power source - Google Patents

Abstract

The fuel cell power source 100 for use in electronic systems includes a fuel cell system 130 and control means 150. The control means 150 calculates the net power requirements of the load device from one or more power function information sources and matches the net power requirements with the power characteristics of the fuel cell system 130 to operate the fuel cell system 130. Determine.

Description

Fuel cell power source

Recently, as the popularity of portability increases, designers of electronic devices have steadily reduced the size and weight of the device. These reductions are, in part, novel such as nickel-metal hydrides, lithium ions, zinc-air, and lithium polymers, which allow large amounts of power to be packaged in small containers. This is made possible by the development of battery chemistries. Secondary or rechargeable batteries should be recharged when their capacity is depleted. Recharging is generally performed by connecting the battery to a battery charger that converts alternating current into a low level direct current of 2 to 12 volts. The charge cycle lasts at least 1 hour to 2 hours, more typically 4 to 14 hours. One drawback of current battery technology is the need for sophisticated charge management and slow charge rates.

Fuel cells are expected to be the main energy sources for portable electronics. Fuel cells catalyze hydrogen molecules into hydrogen ions and electrons and then oxidize the hydrogen ions to H ₂ O to extract the byproduct water, extracting the electrons as power through a membrane. One advantage of fuel cells is the ability to provide significantly larger amounts of power in a smaller package compared to conventional batteries. Their potential ability to provide long talk time and standby times in portable communication device applications is motivating continued miniaturization of fuel cell technologies. For example, polymer electrolyte membrane (PEM) based air-breeding, air-breathing, dead-ended fuel cells are ideally suited for powering portable communication devices and other portable electronic devices.

In the case of a conventional battery powered electronic device, the operating characteristics and the usage pattern of the electronic device do not significantly affect the efficiency, reliability or lifetime of the battery. On the other hand, when a fuel cell system is used as a power source for an electronic device, most of the basic physical, electrochemical and electrical characteristics of the fuel cell system vary permanently or temporarily by the usage pattern of the electronic (load) device. This change in fuel cell system characteristics directly affects the performance and service life of the fuel cell power source. Average dynamic peak load patterns of the electronic device also affect the fuel consumption and conversion efficiency of the fuel cell system. Current generation of digital, multifunctional electronic devices is sharp and has variable duty cycles consisting of short duration power spikes followed by long duration low power requirements. Optimizing fuel cell power supplies for this class of electronic devices is a complex process that involves constantly obtaining individual user usage patterns, dynamic power requirements of the electronic device itself, and operating characteristics of fuel cell systems.

The current technology solves some aspects of this problem related to hybrid powered vehicles consisting of battery and fuel cell systems. For example, to Rajashekara, US Patent 6,321,145, entitled "Method and apparatus for a fuel cell propulsion system," issued November 20, 2001, selects power from a battery or fuel cell system depending on the current operating conditions of the vehicle. It teaches how to use it. Similar methods and apparatus are disclosed in US Pat. No. 5,808,448, entitled “Method and apparatus for operating an electric vehicle having a hybrid battery,” issued September 15, 1998 to Naito.

Although the methods of the current technology solve the problem of sharing the load between fuel cells and batteries as they relate to hybrid power sources, these methods do not perform the operation of fuel cell power sources based on the dynamic power requirements of electronic devices. It does not solve the key problem of optimizing. In addition, these methods do not provide the performance effects of the usage profile of the load device for a fuel cell based power source.

Therefore, what is needed is a method and apparatus for considering and balancing the power characteristics of a fuel cell system, the dynamic load requirements of electronic devices, and the usage profile of one or more device users for use of the fuel cell system as a power source for a wide range of load devices. .

The invention is illustrated by the embodiments illustrated in the accompanying drawings, in which like reference characters designate the same components, but are not limited to these.

The present invention relates generally to fuel cell power sources, and more particularly to a method and system for operating a fuel cell power source.

1 to 3 are block diagrams of various embodiments of a fuel cell power source according to the present invention.

4 is a process flow diagram of the operation of a fuel cell power supply in accordance with a preferred embodiment of the present invention.

As required, detailed embodiments of the invention are disclosed herein, but it should be understood that the disclosed embodiments are merely examples of the invention, which can be embodied in various forms. Therefore, the specific structural and functional details disclosed herein are to be interpreted as illustrative rather than limiting, and as a basis for teaching those skilled in the art to variously employ the present invention in any suitable detail construction as a basis for the claims. In addition, the terms and phrases used herein are not intended to be limiting but rather to provide an understandable description of the invention.

Described herein are apparatus and methods for efficiently operating a fuel cell power source for a load device. The method and apparatus balance three major factors that affect the operational behavior of a fuel cell power source. The dynamic load requirement of the load device and the usage profile of one or more device users, which are referred to as power function sources, constitute the first two elements, and the power characteristic of the fuel cell system constitutes the third element. A method of efficiently operating a fuel cell power source includes capturing a usage profile of one or more device users of a load device over a period of time, and based on the dynamic load characteristics of the device, each user profile to the actual power requirements of the load device. Converting and selecting operating parameters of the fuel cell system based on the calculated load requirements of the load device.

The current-voltage (I-V) relationship of fuel cell power sources differs greatly from conventional chemical cell power sources such as lithium ion, lithium polymer, nickel metal hydrate and nickel cadmium batteries. The power conversion and fuel utilization efficiency of the fuel cell is closely related to the operating point on the I-V curve. In fuel cell power sources, the energy storage and energy conversion sides are separated. The optimal operation of the fuel cell power source depends not only on the theoretical conversion efficiency of the fuel cell but also on external power load patterns. In fuel cell use devices, small differences in surface in use profiles can have a significant impact on fuel use and overall system conversion efficiency. As an example, consider user A and user B as two cellular telephone users. Two users typically use the phone for eight hours each day. At these eight hours, each user's cell phone transmits for two hours and waits for six hours. User A tends to have long phone calls followed by long rests, while user B makes a few calls during the day, each time only continuing for a few minutes, with little rest between calls. The fuel cell system in user A's fuel cell power source will cycle between the cool standby state and the hot transfer state during long transmissions. The fuel cell system in user B's fuel cell power source will cycle more frequently but to a smaller range and will never reach the high temperature levels experienced by the fuel cell system in user A's fuel cell power source. Fuel cell systems operating in this mode, where power is drawn more frequently with smaller temperature cycles, will be more efficient and provide more operating time to the load device for a given amount of fuel. Therefore, user B will experience more conversations per unit of fuel than user A. Thus, the fuel cell system operating parameters required for user A are very different from what is needed for user B to realize optimal performance of the fuel cell power source.

1 illustrates a fuel cell power supply 100 for providing power to a load device 160 in accordance with a preferred embodiment of the present invention. The fuel cell power source 100 includes a fuel storage container 110 used as a fuel source, a fuel storage container controller 120 controlling the fuel storage container 110, a fuel cell system 130, an information storage device 140, And control means 150 for controlling the operation of the other components in the fuel cell power source 100. Those skilled in the art will appreciate that fuel cell system 130 may include one or more individual fuel cells coupled to one another. Fuel cell system 130 may optionally include supporting peripheral elements such as electrical output regulation circuits, cooling systems, fans, pumps, valves, and regulators. Control means 150 typically includes computing means 170, such as a microprocessor, that can perform arithmetic and logical operations and also communicate with other electrical circuit elements. Preferably, the calculation means 170 is similar to the MC68328 microcontroller manufactured by Motorola, Inc. of Schaumburg, Illinois. It is appreciated that other similar microprocessors may be used for the calculation means 170 and additional microprocessors of the same or alternative type may be added when needed to handle the processing requirements of the calculation means 170. will be. The fuel cell system 130 is coupled to the fuel storage container 110, the control means 150 and the load device 160. The control means 150 is also coupled to the load device 160, the information storage device 140, and the fuel storage controller 120. The information storage device 140 is also coupled to the load device 160. Those skilled in the art will appreciate that information storage device 140 may include random access memory (RAM), read-only memory (ROM), electrically erasable and programmable read-only memory (EEPROM), or equivalents. Will know. Those skilled in the art will appreciate that the information storage device 140 may alternatively be embedded within the control means in accordance with the present invention.

As shown in FIG. 1, the fuel cell power source 100 is coupled to a load device 160 that operates using power from the fuel cell power source 100. Those skilled in the art will appreciate that the load device 160 according to the present invention may be a handheld computer, a laptop computer, a palmtop computer, a personal digital assistant, a power tool, a mobile phone, a mobile radio data terminal, or a mobile cellular phone with a data terminal. It will be appreciated that it could be a phone or an interactive pager such as "Page Writer 2000X" by Motorola Inc. of Schaumburg, Illinois. In the following description, the term "load device" refers to either the foregoing or any equivalent load device. In most embodiments of the specification, a cell phone is described as a load device, but the present invention is not limited to cell phones. Any device capable of being powered by a fuel cell power source can be used within the scope and structure of the present invention.

When the fuel cell power supply 100 starts to operate, the control means 150 searches the information storage device 140 to verify that there is data regarding the dynamic load patterns of the connected load device 160. The startup sequence ensures that data relating to the load device usage pattern of one or more users and the power characteristics of the fuel cell system 130 can be obtained from the information storage device 140. When data relating to the load pattern of the load device 160 is missing, the control means 150 finds out this information in the combined load device 160 and stores it in the information storage device 140 for subsequent use. . In one embodiment, the control means 150 queries the load device 160 for the identity of the current device user of the load device 160. When the device usage pattern of the current device user of the combined load device 160 or the power characteristics of the fuel cell system 130 are missing, the values specified for the parameters associated with this data stored in the information storage device 140 are lost. Used by the control means 150. The control means 150 also begins to record the usage pattern of the load device 160 and the power characteristics of the fuel cell system 130 by the current device user. Once enough information has been recorded, these values are stored in the information storage device 140 for future use. Those skilled in the art will appreciate that a plurality of device user usage patterns of a plurality of device users for one or more load devices may be stored in the information storage device 140 in accordance with the present invention.

The control means 150 calculates the net power load requirement of the load device 160 by combining and matching the dynamic load requirement of the load device 160 with the usage pattern history of the specified device user. Once the net power requirements are known, the control means 150 establishes an initial operating point for the fuel cell system 140 by matching the net power requirements with the power characteristics of the fuel cell system 130. The control means 150 continuously adjusts the operating point of the fuel cell system when the load patterns and the state of the fuel cell power supply 100 change over time.

As an example, when the load device 160 is a cellular telephone, the dynamic load requirements may include peak transfer current, duration and frequency of the transfer current, standby current and sleep mode current. For cell phone applications, most of these parameters are the protocol used by cell phones (ie, code division multiple access (CDMA), time division multiple access (TDMA), and Global System for Mobile Communications (GSM)), cell phone operation The mode, the operating frequency band of the cell phone, the applications running on the cell phone and the region in which the cell phone operates are determined. Those skilled in the art will appreciate that the dynamic load requirements can be any combination of the requirements described herein or equivalent according to the present invention.

The device user usage pattern for a cell phone may include the number of calls made within a specified time period, the frequency of calls made, the duration of each call and the types of services used (voice versus data). Similarly, usage pattern parameters of cell phones may also include standby mode time, speaker volume, backlight usage, mode of operation (eg TDMA vs GSM) and notification mode (vibration versus ringer). The usage pattern also takes into account the special circumstances unique to multifunctional, data-centric cell phones, such as always-on connections, streaming video and audio services, and additional power usage from video games. The present invention stores data corresponding to usage pattern parameters for each device user of each load device in information storage device 140. Those skilled in the art will appreciate that the usage pattern parameters can be any combination of the parameters or equivalents described herein in accordance with the present invention.

The power characteristics of the fuel cell system 130 determine the type of fuel and oxidant supply system, fuel cell structure, electrolyte, electrode, gas diffusion and catalyst materials used and assembly and placement that determine the system response time and efficiency of the fuel cell. Type of approach, age of fuel cell, load capacity, IV curve, and operating pressure, temperature, and moisture of fuel cell system 130. Those skilled in the art will appreciate that the power characteristics of fuel cell system 130 may be any combination of the features and equivalents described herein in accordance with the present invention.

Setting the operating point of the fuel cell system 130 includes selecting the current-voltage output relationship of the fuel cells embedded in the fuel cell system 130, controlling stoichiometry and ratio of reactants, electrolyte Managing the hydration level of the over-product water generation and the purging cycle for decontamination in the case of dead-ended fuel cells. When the control means 150 sets an operating point, the operating voltage and current output of the fuel cells embedded in the fuel cell system 130 are changed such that the fuel cells operate at the most efficient portion of the I-V curve. The concept of these I-V curves is known in the fuel cell art that the I-V curves relate to fuel cells and various parameters of the fuel cell that affect the operating point on the I-V curve. For example, US Pat. Nos. 6,300,000, 5,290,641, and 5,023,150 describe the nature and characteristics of fuel cell I-V curves. Control means 150 may vary the amount of fuel and oxidant that reaches the fuel cell to control the reaction rate and product water generation. In fuel cell systems with active elements such as fans, blowers, pumps, cooling systems and similar components, the control means 150 controls the power output of the fuel cells to load dynamic characteristics of the load device 160. And parameters of these components to match the usage pattern of the device user.

Preferably, in accordance with the present invention, additional functions may be implemented to enhance and validate the three dimensions used by the control means 150 for operating the fuel cell system 130. The control means 150 performs a series of test sequences on the fuel cells embedded in the fuel cell system 130 at startup to ensure that the fuel cell system power characteristics stored in the information storage device 140 are valid and current. do. Test sequences may include tests for internal impedance of fuel cells, current and voltage output of fuel cells under standard load conditions, and the level and age of hydration of the electrolyte membrane. If necessary, the control means 150 will update the parameters defining the power characteristics of the fuel cell system 130 stored in the information storage device 140.

In the second embodiment of the present invention, in addition to operating the fuel cell power supply 100 to optimally match the output requirements, the control means 150 also controls the amount of power capacity remaining in the fuel cell power supply 100. Estimate. The measurement of remaining capacity depends not only on accurately measuring the amount of fuel remaining in the fuel storage container 110 but also on accurately predicting external power load patterns and operating points of the fuel cell at these load conditions. The current generation of digital, multifunctional electronic devices has sharp duty cycles of varying duty cycles consisting of short duration power spikes followed by long duration low power requirements. For this class of load devices, calculating the remaining energy capacity keeps an eye on the usage patterns of each individual device user, the dynamic power requirements of the load device 160, and the power characteristics of the fuel cell system 130. And measuring the amount of fuel remaining in the fuel storage container 110 is a complicated process. Since the control means 150 of the fuel cell power source 100 can already obtain this information, the second embodiment of the present invention uses this feature to implement an accurate fuel measurement function for the fuel cell power source 100. do. The remaining capacity is continuously measured when the load device 160 is in operation to provide the user with the current state of the fuel cell power supply 100. In addition, the feedback provided to the device user preferably relates to the amount of time that the load device 160 will operate in its various modes of operation with usable energy conservation.

2 illustrates another embodiment of a fuel cell power source 200 for providing power to a load device 160 in accordance with the present invention. The fuel cell power source 200 is coupled to the fuel storage container 110 and the fuel storage container 110 used as a fuel source, the fuel storage container controller 120 and the fuel storage container 110 controlling the fuel storage container 110. Coupled to the fuel cell system 130, the information storage device 140 coupled to the load device 160, and the fuel cell power source 130 and the information storage device 140 within the fuel cell power source 200. Control means 150 for controlling the operation of the other components. The control means 150 preferably also provides fuel measurement information to the load device 160 in accordance with the present invention. Those skilled in the art will appreciate that fuel cell system 130 may include one or more individual fuel cells connected to one another. Preferably, the fuel cell power source 200 shown in FIG. 2 also includes measuring means 210 coupled to the control means 150. The measuring means 210 is preferably such as a microprocessor circuit that can calculate the remaining capacity of the fuel cell power source 200 using the net power requirements of the load device 160 and the power characteristics of the fuel cell system 130. It consists of a processing means 220. Preferably, the processing means 220 is similar to the MC68328 microcontroller manufactured by Motorola, Inc. of Schaumburg, Illinois. It is appreciated that other similar microprocessors may be used for the processing means 220 and additional microprocessors of the same or alternative type may be added when needed to handle the processing requirements of the processing means 220. will be. In addition, a communication means 230 coupled to the processing means 220 is also included in the measuring means 210. The communication means may be implemented using additional electrical circuit elements that selectively transmit information from the microprocessor circuitry within the processing means 220 to the load device 160 via the control means 150.

The fuel cell power source 200 is coupled to the load device 160 via the fuel cell system 130, the information storage device 140 and the control means 150. The load device 160 operates by using the power provided by the fuel cell power source 200. When the fuel cell power source 200 starts to operate, the control means 150 searches the information storage device 140 to verify that there is data regarding the dynamic load patterns of the connected load device 160. The startup sequence ensures that data relating to the load device usage pattern of one or more users and the power characteristics of the fuel cell system 130 can be obtained from the information storage device 140. When data relating to the load pattern of the load device 160 is missing, the control means 150 finds out this information in the attached load device 160 and stores it in the information storage device 140 for later use. do. In one embodiment, the control means 150 queries the load device 160 also for the identity of the current device user of the load device 160. When the device usage pattern of the current device user of the combined load device 160 or the power characteristics of the fuel cell system 130 are missing, the values specified for the parameters associated with this data stored in the information storage device 140 are lost. Used by the control means 150. The control means 150 also begins to record the load device usage pattern and power characteristics of the fuel cell system 130 by the current device user. Once enough information has been recorded, these values are stored in the information storage device 140 for future use. Those skilled in the art will appreciate that a plurality of device user usage patterns of a plurality of device users for one or more load devices may be stored in the information storage device 140 in accordance with the present invention.

The control means 150 calculates the net power load requirement of the load device 160 by combining and matching the dynamic load requirement of the load device 160 with the usage pattern history of the current device user. Once the net power requirement is known, the control means 150 establishes an initial operating point for the fuel cell system 140. The control means 150 continuously adjusts the operating point of the fuel cell system 130 when the load patterns and the state of the fuel cell system 130 change with time. Also, as part of the startup sequence, control means 150 queries fuel reservoir controller 120 to obtain the value of fuel remaining in fuel reservoir 110. Control means 150 using information regarding the power characteristics of fuel cell system 130, the dynamic load requirements of load device 160, the usage pattern of the device user, and the amount of fuel remaining in fuel reservoir 110. Calculates fuel measurement information such as power capacity remaining in the fuel cell power source 200, the amount of time that the load device 160 may be operated in different modes, fuel consumption rate and energy conversion efficiency. Those skilled in the art will appreciate that fuel measurement information may comprise any combination of the information or equivalents described herein in accordance with the present invention.

The method for measuring the remaining capacity may be based on the fuel cell system 130 based on the remaining fuel amount by referring to a look-up table or equation indicating a device usage profile for a specific device user of the load device 160 stored in the information storage device 140. And calculating an expected operating time of the load device 160 by estimating the remaining energy capacity of the fuel cell and estimating the conversion efficiency of the fuel cell system 130 corresponding to the user profile. The remaining operating time of the load device 160 is measured using the changes in efficiency and I-V operating point for a given output load that characterize the particular fuel cell system 130. The remaining capacity parameters calculated by the control means 150 may be displayed to the device user via the device user interface element 250 in the load device 160 or the user interface element 240 or equivalent in the fuel cell power source 200. have.

In devices operated with fuel cells, small differences between usage models can greatly affect fuel usage and overall fuel cell system conversion efficiency. For example, consider user A and user B as two cellular telephone users. Two users typically use their cell phones for eight hours each day. At these eight hours, each user's cell phone transmits for two hours and waits for six hours. User A tends to have a long phone call followed by long rests, while User B makes a few calls during the day, only a few minutes each time, and few rests between calls. The fuel cell system in user A's fuel cell power source will cycle between the cool standby state and the hot transfer state during long transmissions. The fuel cell system in user B's fuel cell power source will cycle more frequently but to a smaller range and will never reach the high temperature levels experienced by the fuel cell system in user A's fuel cell power source. Fuel cell systems operating in this mode, where power is drawn more frequently with smaller temperature cycles, will be more efficient and provide more operating time to the load device for a given amount of fuel. Therefore, user B will experience more talk time per unit of fuel than user A. Thus, the fuel gauge used to estimate the remaining capacity of the fuel cell power source 200 for the load device 160 uses different usage models for user A and user B for improved prediction accuracy.

Preferably according to the invention, further functions can be implemented to enhance and validate the three dimensions used by the control means 150 for operating the fuel cell system 200 and to calculate fuel measurement information. The control means 150 performs a series of test sequences on the fuel cells embedded in the fuel cell system 130 at startup to ensure that the fuel cell system power characteristics stored in the information storage device 140 are valid and current. do. Test sequences may include tests for internal impedance of fuel cells, current and voltage output of fuel cells under standard load conditions, and hydration level and age of the electrolyte membrane. Those skilled in the art will appreciate that the tests may include any combination of those described herein or equivalents in accordance with the present invention. If necessary, the control means 150 will update the parameters defining the power characteristics of the fuel cell system 130 stored in the information storage device 140.

In a third embodiment of the invention, the measuring means estimates the power capacity remaining in the fuel cell power source. 3 shows a third embodiment of a fuel cell power source 300 for providing power to a load device 160 according to the present invention. The fuel cell power source 300 is coupled to the fuel storage container 110 and the fuel storage container 110 used as a fuel source, the fuel storage container controller 120 and the fuel storage container 110 which control the fuel storage container 110. ), A fuel cell system 130 coupled to the load cell 160, an information storage device 140 coupled to the load device 160, and measurement means 210 for providing fuel measurement information to the load device 160. Those skilled in the art will appreciate that fuel cell system 130 may include one or more individual fuel cells connected to one another. The measuring means 210 coupled to the information storage device 140, the fuel cell system 130 and the fuel storage container controller 120 preferably comprises the net power requirements of the load device 160 and the fuel cell system 130. And processing means 220, such as a microprocessor, that can calculate the remaining capacity of the fuel cell power source using the power characteristic of.

The fuel cell power supply 300 is coupled to a load device 160 that operates using the power provided by the fuel cell power supply 300. When the fuel cell power supply 300 starts to operate, the measuring means 210 searches the information storage device 140 to verify that there is data concerning the dynamic load patterns of the connected load device 160. The startup sequence ensures that data relating to the load device usage pattern of one or more users and the power characteristics of the fuel cell system 130 can be obtained from the information storage device 140. When data relating to the load pattern of the load device 160 is missing, the measuring means 210 finds out this information in the attached load device 160 and stores it in the information storage device 140 for later use. do. In one embodiment, the measuring means 210 queries the load device 160 also for the identity of the current device user of the load device 160. If the usage pattern of the device user or the power characteristics of the fuel cell system 130 are missing, the default values for the parameters associated with this data, stored in the information storage device 140, are used by the measuring means 150. The measuring means 210 also begins to record the load device usage pattern and power characteristics of the fuel cell system 130 by the current device user. Once enough information has been recorded, these values are stored in the information storage device 140 for future use. Those skilled in the art will appreciate that a plurality of device user usage patterns of a plurality of device users for one or more load devices may be stored in the information storage device 140 in accordance with the present invention.

The measuring means 210 calculates the net power load requirement of the load device 160 by combining and matching the dynamic load requirement of the load device 160 with the usage pattern history of each device user. In addition, as part of the startup sequence, the measuring means 210 queries the fuel reservoir controller 120 to obtain a value of the fuel remaining in the fuel reservoir 110. Using information about the power characteristics of the fuel cell system 130, the dynamic load requirements of the load device 160, the usage pattern of the device user, and the amount of fuel remaining in the fuel storage container 110, the measuring means 210 can Calculate fuel measurement information such as the remaining power capacity of the fuel cell power source 300, the amount of time the load device 160 may be operated in other modes, fuel consumption rate and energy conversion efficiency. Those skilled in the art will appreciate that fuel measurement information may comprise any combination of the information or equivalents described herein in accordance with the present invention. The remaining capacity parameters calculated by the measuring means 210 may be displayed to the device user via the user interface element 250 in the load device 160, the user interface element 240 in the fuel cell power source 300, or an equivalent. have.

4 is a flow chart of a process used to manage the performance of a fuel cell power source in accordance with the present invention. In FIG. 4, rectangular boxes represent structural entities in the process, and rounded boxes represent process steps for achieving various structural entities. In FIG. 4, the process flow begins at step 400 where counter " n " is set to one. The process then goes to decision point 405, which confirms the operation of the load device 160 by the nth device user. If yes is returned at the decision point, the process flow may cause the fuel cell power source 100, 200 to verify that there is data regarding the dynamic load patterns of the connected load device 160. Continuing with the initialization step 410 to query. The initialization step also ensures that data regarding the load device usage pattern of the nth user and the power characteristics of the fuel cell system 130 can be reliably obtained. If data on the load pattern of the load device 160 is missing, the control means 150 queries the attached load device 160 for this information and stores it in the information storage device 140 for later use. . When the usage pattern of the n-th user or the power characteristic of the fuel cell system 130 is missing, the default values for the parameters associated with this data stored in the information storage device 140 are used by the control means 150. do. The net power load requirement of the load device 160 is calculated 420 by matching the parameters associated with the dynamic load requirements of the load device 160 with the usage pattern of the nth device user. In a next step 430, the control means 150 matches the net power requirements with the power characteristics of the fuel cell system 130 stored in the information storage device 140 and, in step 440, the fuel cell power source 100. Select the settings for the operation. Control means 150 uses the selected parameters to operate fuel cell system 140 at target conditions (460). Next, in step 470, the counter "n" is incremented. The process then returns to decision point 405 and continues checking the user state until it returns "no" at decision point 405, and if no, the process flow ends at end point 480. .

Those skilled in the art will appreciate that the application of the method as shown in FIG. 4 for operating a fuel cell power supply is not limited to any particular type of load device. Some applications of this method to electronic devices are described herein. Examples of non-electronic device applications include fuel cell use or hybrid electric vehicles. Each driver of a car has a different driving style, and therefore has a different effect on fuel efficiency. Useful parameters that make up the usage profile for this application include post-stop acceleration, average speed, stop frequency, acceleration variability, cruise control usage, and many more. The present invention is an improvement over recent vehicles, whether using gas, hybrid, electric or fuel cells, in that it is tailored to each driver and tailored to fuel efficiency.

Although the present invention has been described in terms of preferred embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made within the present invention. Accordingly, such changes and modifications are considered to be within the spirit and scope of the invention as set forth in the appended claims.

Claims (10)

In a fuel cell power source, A fuel cell system providing power to the load device; And Control means coupled to the fuel cell system and coupled to the load device, The control means, Calculate one or more net power requirements of the load device from one or more power functional information sources, A fuel cell power source programmed to select an operating point of the fuel cell system by matching one or more net power requirements with one or more power characteristics of the fuel cell system. The method of claim 1, And an information storage device coupled to the control means and coupled to the load device for storing one or more parameters associated with the power function information sources and power characteristics of the fuel cell system. The method of claim 3, wherein And said control means comprises calculating means for calculating one or more parameters associated with said power function information sources and the power characteristic of said fuel cell system. In a fuel cell power source, A fuel cell system providing power to the load device; Control means coupled to the fuel cell system, coupled to the load device, coupled to a fuel storage vessel controller, the one or more net power requirements of the load device calculated from one or more power functional information sources, the one or more net The control means programmed to select an operating point of the fuel cell system by matching power requirements with one or more power characteristics of the fuel cell system; And A fuel cell power source comprising measurement means coupled to the control means, the measuring means programmed to calculate the remaining capacity of the fuel cell power source using one or more power requirements of the load device and one or more power characteristics of the fuel cell system . The method of claim 4, wherein The control means, Calculation means for calculating one or more parameters associated with the power function information sources and power characteristics of the fuel cell system, and And an information storage device, coupled to the calculating means, for storing one or more parameters associated with the power function information sources and power characteristics of the fuel cell system. The method of claim 4, wherein The measuring means, Processing means for measuring residual fuel information from the control means and combining the residual fuel information with the net power requirements of the load device and the power characteristics of the fuel cell system to estimate the remaining capacity of the fuel cell power source; And And communication means for transmitting said remaining capacity of said fuel cell power source to said control means. The method of claim 4, wherein And a user interface element for displaying the remaining capacity of the fuel cell power source. In a fuel cell power source, A fuel cell system providing power to the load device; And Measuring means coupled to the fuel cell system, coupled to the load device, coupled to a fuel storage vessel controller, The measuring means, Calculate one or more net power requirements of the load device from one or more power function information sources, And calculate a remaining capacity of the fuel cell power source using one or more net power requirements of the load device and one or more power characteristics of the fuel cell system. The method of claim 8, The measuring means, Measure residual fuel information from the fuel storage vessel controller and combine the residual fuel information with one or more net power requirements of the load device and one or more power characteristics of the fuel cell system to estimate the remaining capacity of the fuel cell power source; Treatment means, and And communication means for transmitting said remaining capacity of said fuel cell power source to said load device. In the method for operating a fuel cell power source, Obtaining one or more power characteristic information sources and one or more power characteristics of the fuel cell system; Calculating net power requirements of the load device from one or more power function information sources; And Selecting an operating point of the fuel cell system by matching one or more net power requirements with one or more power characteristics of the fuel cell system.